I think it's the same piece as the Bug Out Gear module. I have a modified version (with a TW0K) in my very favorite 2 cell light. It puts out a large hotspot and a nice spillbeam. I had a stock one and was a bit disappointed with the brightness and the tint. (For the record, my stock one was from Bug Out Gear, not G&P). It wasn;t bad, just not as good as I was expecting. I basically wanted something with a hotspot and throw similar to the Inova T3/X03 but with a nice smooth spillbeam and that is exactly what my modded one gives.
It can run on 2 or 3 primary 123 cells, and on one or two R123 or LiON cells. I run mine in a Vital Gear 2 cell body and usually on a 17670 cell, sometimes on 2 MP R123 cells.